docs: def _get_template_from_string(self, ostmpl):
          '''
          Get a jinja2 template object from a string.
          :param ostmpl: OSConfigTemplate to use as a data source.
          '''
          self._get_tmpl_env()
          template = self._tmpl_env.from_string(ostmpl.config_template)
          log('Loaded a template from a string for {}'.format(
              ostmpl.config_file),
              level=INFO)
          return template